1. Field of the Invention
This invention relates to a reel driving device for use in the slot machine in which a reel is driven by a pulse motor or the like.
2. Related Background Art
In the conventional slot machine, reels are started to rotate by a rotating force caused by an impact force mechanically given by a lever operation and is caused to stop rotating by locking a paw preset for each symbol of each reel by pushing, e.g. a stop button. For judging a combination of symbols, the symbols of each reel have different signal grooves, and when the reels are stopped, a combination of symbols are judged based on their signal grooves.
But the conventional mechanically driven slot machine has a number of mechanical parts, which makes its structure complicated with results that costs are high and it is difficult to retain precision in fabricating them.
In view of such problems, recently the slot machine which is driven by the pulse motor has been used. In such slot machine, a signal for actuating the pulse motors of respective reels is generated by a lever operation to cause the pulse motors to rotate the reels, and the reels are stopped based on a signal for stopping the respective pulse motors generated by pushing a stop button. Symbols of the respective reels are judged by counting driving pulses supplied to the respective pulse motors and judging a combination of the counted signals by a microcomputer (Japanese Utility Model Publication No. 7268/1988, Japanese Utility Model Laid Open Publication No. 115566/1982 and U.S. Pat. No. 4,410,178).
Compared with the conventional mechanically driven slot machine, such pulse motor driven slot machine, in which the counted signal of the driving pulses is processed by a microcomputer to judge the symbols of the respective reels, has lower costs, lower possibility of abrasion and a drastically improved structure.
But, the pulse motor, which has a small torque with respect to a load of the reel accelerates the rotation of the reel considerably so lower compared with the mechanical drive that the rotation of the reel is not regular (awkward) and has low acceleration. That is, this results in a problem of poorer images compared with the mechanically driven slot machine.
Another problem with the pulse motor driven slot machine is that when the input of pulses to a pulse motor driving circuit is stopped to stop the pulse motor abruptly, the reel deviates at its stop position due to its inertia.